Here a Fish,  There a Fish - Killifish

Research Question: How and why do Killifish populations change along the Poquonnock River?

Part A: Read the background information

Both banded killifish (Fundulus daphanus) and striped killifish (Fundulus majalis) can be found in the Poquonnock River estuary.  The banded killifish is primarily a fresh water fish, but sometimes they venture down into brackish (partly salty) water. Banded killifish prefer quiet water and mud, gravel, and sandy bottoms with abundant vegetation and places to hide. The eggs stick to submerged vegetation during spawning in late spring and summer. The striped killifish can be found in abundant schools in shallow coastal shoreline waters and salt marsh creeks, but is rarely found in fresh water. Females bury eggs in the sand or mud near the low tide level, or in tide pools. The diet of both types of killifish consists of small invertebrates.


Unfortunately, the students who conducted the study did not record which species of killifish they captured in their seine nets.

Part B: Prediction and Reasoning

Study the background information provided on Killifish (above), and take the virtual tour of the Poquonnock River, paying close attention to habitat descriptions.  Write answers to the following prompts on your sheet of paper.

  1. Make a prediction:  In July, where along the Poquonnock River would you expect to see the most banded killifish?  The most striped killifish?

  2. Explain your reasoning:  WHY do you think killifish are most likely to be in this location?

Part C: Analyze the Data

Look at the dataset below.  On your piece of paper, illustrate the data by making a graph.  Your graph should have clear labels on both the x-axis and the y-axis.  The type of graph (scatterplot, column graph, etc) is up to you.

This table shows the number of killifish captured while seining at each location, on a single day in July 2019.  

 Part D: Interpret the Results and Make Arguments from Evidence

On your sheet of paper, answer the following questions:

  1. Make a claim that answers the research question (one sentence).

  2. What evidence was used to write your claim? Reference specific parts of your graph.

  3. Explain your reasoning. Make sure to connect your answer to what you have learned about the biology of killifish.

  4. Was your prediction supported by the results? Use evidence to explain why or why not.

  5. How would you follow up? Describe a new question that should be investigated to build on these results, and what future data should be collected to answer your question.

Congratulations!  Your final analysis should include the following components:

  • A statement of the research question that you chose/were assigned

  • Your prediction and your reasoning

  • Your labelled graph

  • Your answers to the results questions

Share your results with your teacher, and/or by emailing it to Project O:, attn: Dr. Molly

**Educators and/or homeschool parents: educator guides are available for all research projects. 

Email to request an educator guide**

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